load data for 300 grain .338 scenar

Re: load data for 300 grain .338 scenar

I've run the 300gr Scenar with 87 grains of Retumbo at 2850 fps from a 27" 1 in 9.4 Rock barrel with great success. Sub MOA out to 1700 meters.

My chamber is CIP length and this load is about max, so I'd start a shorter OAL load at 84 or so and work up.

Cory Trapp
Gunsite Academy, Inc.
 
Re: load data for 300 grain .338 scenar

thanks cory, ill give that a try.

i was hoping to get 2750 to 2800 fps without pushing the envelope too much.

what range do you test at for load development for the .338 lm?

thanks again, ill post my results as i go!
 
Re: load data for 300 grain .338 scenar

I do initial testing at 500 meters, If that does not produce a group under 2.5" it's not worth messing with any further. I'd expect you can get at least 2750 with a safe load at an OAL of 3.635".
 
Re: load data for 300 grain .338 scenar

300 SMK out of my 338 RUM,Rock barrel 1-9.4 twist 87.5gr RE25 2800FPS REM 9.5 primer.Shoots bug hole at 100 yds and shot a 7"&9" groups back to back at 1000yards superbowl sunday with it.My best off record was 4-7/8" all 5 shot groups.Load is brass friendly.If I push it to 2950 or above it still shoots but the brass is good for 1 shot.
 
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Re: load data for 300 grain .338 scenar

wow this place is fast, I went back in and edited that to 88, 10 mins after realising I had a brain fart and posted the 250 grain load and already there are questions on it. I am impressed.

Sorry for the crap info in the first place.

Ewen
 
Re: load data for 300 grain .338 scenar

The chamber and magazine in that particular gun is set for CIP length, which is 3.681. That leaves me about a .02 jump in that gun with the 300 Scenar. The 250 grain bullet get loaded just a bit shorter, to keep base to ogive at 2.92 or so. That's why I said to start lower, I've got a little more case space with that setup.
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kchu02</div><div class="ubbcode-body">anyone use H4831SC with the 300gr scenars?

Kevin </div></div>


Use RL25. H4831SC, IMO, is too fast for such a heavy bullet.
 
Re: load data for 300 grain .338 scenar

I shoot the 300 SMK's over 86 grain of REL 25 and the 250 Scenars over 89 - 91 grains of REL 25. I love REL 25 it is by far the most consistent powder I have tested, others I have used are H1000, Retumbo. Vitaurvori is supposed to be very nice too.
 
Re: load data for 300 grain .338 scenar

Ok thanks for the info- having the hardest time finding RL25 at stores around me
frown.gif


might be forced to order from online and get hammered by the fee
 
Re: load data for 300 grain .338 scenar

pgs:

Any particular reason you would not consider shooting the 250gr scenars instead of the 300gr?

I do not shoot a 338LM but have friends that are instructors for Finland Military and last years Finnish Sniper Champion and they both shoot the 250gr scenars and have done so out to 2000yds from a factory TRG42.

Thanks
 
Re: load data for 300 grain .338 scenar

Later,

thats a good question. i just picked up my brand new GAP surgeon action .338 lm on thursday. its now broke in (41 shots). during break in it shot the 250s really well. at 100m they were going .2 and .3 with vvn560, 84 to 86 grns. the loads were slow, only 2800 or so but i see real potential with the 250s. if i can get a reliable load to go 3000 fps it will stay super-sonic to about 1800 meters at my elevation.

my barrel is a MTU contour 28" long with a 1 in 9.75 twist bartlein 5r. its in an A-5 mac stock with badger detach bottom metal and A-I mags. the 250s seem to shoot best when jumped 50 to 60 thoa. scope is a 5-25 S&B PMII with P4 fine reticle mrad. im about to sit down and load some 250s with RL25. ill report back in the next day or two.

thanks everyone for all the help!!
 
Re: load data for 300 grain .338 scenar

From my past load developement for a SAKO TRG-42 .338 Lapua Magnum, try using 87.5 - 88.5 grains of VihtaVuori N-165 powder using either 250 grain bullets or possibly even 300 grain bullets. Obviously, you should start several grains of powder lower and work your way up. But the accuracy results I was able to obtain were the best and most consistant of any rifle I've shot.

Good Shooting!
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: kchu02</div><div class="ubbcode-body">Ok thanks for the info- having the hardest time finding RL25 at stores around me
frown.gif


might be forced to order from online and get hammered by the fee </div></div>


So buy 20 or 30 lbs and be done with it-or share the hazmat with a friend and stock up on powder. At 80-90 grains a pop-you need BIG ass bottles.
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pc3</div><div class="ubbcode-body">Will a 10 twist shoot these lapua 300 gr pills ??

My build will have a 10 twist Lilja on it ?? </div></div>

Yes.
 
Re: load data for 300 grain .338 scenar

I have an .338 Edge with a 10 twist Lilja and it shoots the 300SMK just fine. I am running 92.0gn of Retumbo. Haven't tried RL-25 yet. I have heard some people were getting lots that were burning faster than RL-22. Anybody else heard that?
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ranger1183</div><div class="ubbcode-body">From my past load developement for a SAKO TRG-42 .338 Lapua Magnum, try using 87.5 - 88.5 grains of VihtaVuori N-165 powder using either 250 grain bullets or possibly even 300 grain bullets. Obviously, you should start several grains of powder lower and work your way up. But the accuracy results I was able to obtain were the best and most consistant of any rifle I've shot.

Good Shooting!
</div></div>

N165 works well with 250 grainers, though its bit too fast if looking for high MV:s.
N170/N560 work fine. Even slower new N570 is true 338LM "supercharger" - but there isnt free lunches.
Amount of heat, erosion and shite in barrel increases quite a bit.
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Amount of heat, erosion and shite in barrel increases quite a bit.</div></div>

Does the 570 reduce the amount of rounds you can fire accurately before you need to clean?

Any numbers on round count (before needing to replace barrel) solely shooting 300 grains compared to 250's?

I have been waiting for VV 570 to land here to buy a bunch, could use some detailed information.
 
Re: load data for 300 grain .338 scenar

range report as follows: worked up a load for the .338 LM and the 300 gr scenar using 96.5 grs of retumbo. average velocity was 2860 fps. tested it out to 1650 meters this morning and very pleased with the results. put 6 shots in a 15" circle.(30" granite glacier rock). cold here today, about 5 above zero . may have to reduce load a bit when it gets warmer. shooting into a slight head wind. good clear air.

very impressed with the 300 scenars. i came up with a bc of .790 through balancing numbers with the JBM program at my velocity.

its supposed to be 15 to 20 below the next few days. when it warms up ill be back out to try it out to 2000 meters.

thanks everyone for all the input!!
 
Re: load data for 300 grain .338 scenar

as a side note i forgot to mention, the 1 in 9.75 twist in my bartlein 5R barrel stabilized that 300 gr scenar beautifully in this cold, dense air.
 
Re: load data for 300 grain .338 scenar

I'm hoping you meant 86.5 of Retumbo, Quickload shows 71K psi for 96 with a 300 gr bullet. I'm close to max pressure at 87.1, loaded to max length, which is still .03 or so off the lands. I'm not even sure I can get 96.5 in the case and still put the 300 grain bullet in at max CIP length.
 
Re: load data for 300 grain .338 scenar

96.5 is what im using. i tried loading 85.0 and was getting smoked necks. wasnt enough pressure to seal the necks to the chamber. hodgdons reloading manuals min load is 85.0 grs and lists that at 41,000 cup and only 2376 fps. they list a max of 94.0 grs for 2671 fps and 52,700 cup.

trust me i worked up slowly and carfully. i had easy bolt lift and round primers up to 97.5 grs. i backed it down a bit and its working fine in my rifle. i expect to make adjustments as our weather gets warmer here.

the last thing i want to do is blow up my brand new GAP rifle!
 
Re: load data for 300 grain .338 scenar

Wow. I get a stiff bolt lift at 97 pushing 250 Scenars, much less the 300, Hodgdon lists 98 at max with the 250 Hornady. I'm looking at the PDF file from the Hodgdon Web site right now, it shows max at 94 grains, compressed, 53,400cup, 2654 from a 24" tube, with the 300 Sierra, which has less bearing surface. Maybe I'm looking at the wrong manual, because it does not show a minimum load. QuickLoad is not usually far off the mark, I'm just amazed that a chamber chould make such a large differance. What's your COAL? How far off the lands are you?
 
Re: load data for 300 grain .338 scenar

coal is 3.595. maybe i have a lot slower lot of retumbo than your using. how can you be getting 2850 with 87 grs? there is something out of whack here. your barrel is shorter and your twist is faster... it just doesnt make sense to me.

anyone else out there have any thoughts on this?
 
Re: load data for 300 grain .338 scenar

Did I write 2850? I look back and see I did, my own typo. It should be 2650. At 3.595, that would be real compressed. 3.641 does not leave much room with 87.1 . I'd also be pretty supprised if the lots were that much different. I've got an 8# jug that should show up in UPS tomorrow or Wed, I'll check that and report back.
 
Re: load data for 300 grain .338 scenar

Desert Fox:

thats a good looking round! ive dabbled with a few ackley designs over the years always liked the mechanical advantage you gain with them.

how did it shoot while you were fire-forming? and what was the load? what rifle is it? are you using A.I. mags? how does that straight case feed?

sorry for all the questions, i just have a soft spot for ackley designs.

thanks, pat
 
Re: load data for 300 grain .338 scenar

I just shoot the regular 338LM load using the 250 grain Sierra SBT hunting bullet...leftover from my 338 Winny. I also used 250 grain SMK with Reloader 25. Fired this 5 shot group @ 110 yards.

Picture174-3.jpg


shot this 3 shot group at 510 yards with 300 SMK

Target001.jpg


The rifle builder is Nathan Dagley of SSG Gunsmithing. It's a single shot Lawton 7500 Action with 30" Broughton. The rifle is not picky at all. I could load any bullet both hunting and match and it shoots really well. I prefer the 300SMK though for longrange shooting. Using the.768 factory published BC, my Exbal trajectory prediction is dead on up to a mile.

Target019.jpg
 
Re: load data for 300 grain .338 scenar

Desert Fox:

thats a nice set up! youve got it shooting sweet!

have you tried the 300 scenar yet?

ps... ive got that same spotting scope! love it!
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pgs</div><div class="ubbcode-body">Desert Fox:

thats a nice set up! youve got it shooting sweet!

have you tried the 300 scenar yet?

ps... ive got that same spotting scope! love it! </div></div>

Nope! Still waiting for the availability. Last time I checked from Grafs, it's still on back-order.

Love the Zeiss too. Just perfect size for all around use.
 
Re: load data for 300 grain .338 scenar

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Desert Fox</div><div class="ubbcode-body">I just shoot the regular 338LM load using the 250 grain Sierra SBT hunting bullet...leftover from my 338 Winny. I also used 250 grain SMK with Reloader 25. Fired this 5 shot group @ 110 yards.

Picture174-3.jpg


shot this 3 shot group at 510 yards with 300 SMK

Target001.jpg


The rifle builder is Nathan Dagley of SSG Gunsmithing. It's a single shot Lawton 7500 Action with 30" Broughton. The rifle is not picky at all. I could load any bullet both hunting and match and it shoots really well. I prefer the 300SMK though for longrange shooting. Using the.768 factory published BC, my Exbal trajectory prediction is dead on up to a mile.

Target019.jpg
</div></div>

Desert Fox that is one bad mother!got anymore good pics of this rifle?wow!
 
Re: load data for 300 grain .338 scenar

300 SMK, my load is 90g of RL25 = 2680fps

Chamber is MIN SAAMI and no turn nk.

Produces this type of group at 100mtrs

300SMK90gRL25SurgeonXL.jpg


91 g is no slouch either!


Tested so far out to 600mtrs.

Fist / head sized rocks are pretty much repetatively boring to shoot.

If shooting ever could become repetively boring that is.